WO2008070778A2 - Pyridoxamine and low molecular weight heparinoids for diabetic kidney disease - Google Patents

Abstract

The present invention provides compositions and methods for treating or inhibiting development of diabetic kidney disease, and/or limiting progression of renal disease.

Description

Pyridoxamine and low molecular weight heparinoids for diabetic kidney disease

Cross Reference This application claims priority to U.S. provisional patent application serial number 60/873,197 filed December 6, 2006, incorporated by referenced herein in its entirety.

Field of the invention This application relates, for example, to the fields of chemistry, medicine, and renal disease.

Background of the Invention

Nephropathy develops in 30 to 40 percent of patients with Type 1 diabetes, and in an estimated 10 to 15 percent of patients with Type 2 diabetes. An early sign of this life -threatening disease includes the loss of protein (particularly albumin) into the urine ("proteinuria" or "albuminuria"). As renal damage progresses, patients lose the ability to effectively filter the blood in the glomerulus and can progress to the need for dialysis or transplantation. Diabetic nephropathy, and in particular dialysis and transplantation, is costly both in terms of medical treatment and in lost productivity. Treatment that prevents or limits the development or progression of diabetic nephropathy, particularly at an early stage will meet a significant medical need and provide significant cost savings to the health care system.

Thus, improved compositions and methods are needed for the treatment of diabetic nephropathy and other diabetic kidney diseases.

Summary of the Invention

In a first aspect, the present invention provides compositions, comprising:

(a) an amount effective of pyridoxamine, or a pharmaceutically acceptable salt thereof for treating diabetic nephropathy; and

(b) an amount effective of low molecular weight heparinoids (LMWH), or a pharmaceutically acceptable salt thereof, for treating diabetic nephropathy. In another aspect, the present invention provides pharmaceutical compositions comprising the composition of any embodiment of the first aspect of the invention and a pharmaceutically acceptable carrier thereof.

In a further aspect, the present invention provides methods for treating or inhibiting development of diabetic kidney disease, and/or limiting progression of renal disease, comprising administering to a hyperglycemic subject in need thereof an amount effective to treat or inhibit development of one or more diabetic kidney diseases, and/or to limit progression of renal disease of any embodiment of the first aspect of the invention.

Detailed Description of the invention

The present invention provides compositions and methods for treating diabetic kidney disease in a subject in need thereof.

In a first aspect, the invention provides a composition, comprising: (a) an amount effective of pyridoxamine, or a pharmaceutically acceptable salt thereof for treating diabetic nephropathy; and

(b) an amount effective of low molecular weight heparinoids (LMWH), or a pharmaceutically acceptable salt thereof, for treating diabetic nephropathy.

Pyridoxamine has been shown to be useful for treating and preventing diabetic kidney diseases including, but not limited to, diabetic nephropathy, proteinuria, impaired glomerular clearance, retinopathy, neuropathy, atherosclerosis, diabetes- associated hyperlipidemia, oxidative modification of proteins, urinary stone disease, obesity-related complications, proliferation or smooth muscle cells in the aorta, coronary artery occlusion, and hypertension; and dialysis-related disorders including dialysis-related cardiac morbidity and mortality, dialysis-related amyloidosis, dialysis-related increases in permeability of the peritoneal membrane in a dialysis patient, renal failure progression in a dialysis patient, and ultrafiltration failure and peritoneal membrane destruction in a dialysis patient. (See, for example, U.S. Patent Serial No. 5,985,857; WO 00/21516; WO 00/23063) "Low molecular weight heparinoids" (LMWH) are a class of glycosaminoglycans typically having an average molecular weight of less than 8000 Da. Many LMWH can be obtained by various methods of fractionation or depolymerisation of polymeric heparin, as is known to those of skill in the art. (See, for example, Linhardt, R.J. Gunay, N. S. (1999). Sem. Thromb. Hem. 25 (3): 5-16.) Other LMWH can be prepared from natural sources; see, for example US 5,496,807, incorporated herein by reference in its entirety. Non-limiting LMWH according to the invention include sulodexide, ardeparin, certoparin, enoxaparin, parnaparin, tinzaparin, dalteparin, reviparin, and nadroparin, pharmaceutically acceptable salts thereof, and combinations thereof.

Sulodexide, a glycosaminoglycan extracted from mammalian intestinal mucosa, has been postulated as useful for the treatment of diabetic nephropathy (Gambaro et al, 2002 (the DiNAS study)) and diabetic retinopathy (See, for example, US 5,496,807 and US 6,080,732), and other LMWH have been identified as potentially useful for inhibiting proteinuria (See, for example, Benck et al., Clin J Am Soc Nephrol. 2007 Jan;2(l):58-67; Ceol et al., J. Am. Soc. Nephrology 11 :2324-2336 (2000); and Myint et al., Diabetes 55:2510-2522 (2006)).

However, it has not previously been proposed to co-administer pyridoxamine and LMWH for the treatment of diabetic kidney disease. Since many pathogenic pathways induced by hyperglycemia contribute to diabetic kidney disease, improved compositions and treatments for diabetic kidney disease are herein postulated to be those that intervene in multiple pathogenic pathways, and which might thereby provide an additive or synergistic therapeutic effect. While not being bound by any mechanism, the inventors believe that the mechanisms of action of LMWH and pyridoxamine against diabetic nephropathy are complementary, with pyridoxamine postulated to, at least in part, reduce the pathogenicity of proteinuria by, for example, lowering the degree of diabetes-induced chemical modifications to albumin and reducing loss of heparan sulfate, while LMWH are postulated to improve the glomerular ultrafiltration barrier through an impact on the integrity of the structure of glycosaminoglycans in the glomerulus that form a charge barrier to retard leaking albumin. Diabetes-induced, chemically-modified albumin is known to induce microvascular disease and increase albumin's pathogenic effect on the tubules. Sulodexide and other LMWH presumably have their primary effect on lowering of proteinuria. (See, for example, Benck et al., Clin J Am Soc Nephrol. 2007 Jan;2(l):58-67; Ceol et al., J. Am. Soc. Nephrology 11 :2324-2336 (2000); Myint et al., Diabetes 55:2510-2522 (2006); US 5,496,807). Thus, the inventors have hypothesized that the use of LMWH, such as sulodexide, and pyridoxamine in combination will both lower proteinuria and reduce its pathogenicity, and therefore give rise to a synergistic effect on the progression of renal disease that develops in diabetic patients.

The compositions of this aspect of the invention include admixtures of the pyridoxamine and LMWH, or pharmaceutically acceptable salts thereof, as well as separate unit dosages of each that are manufactured for combinatorial use. Such separate unit dosages may be administered concurrently or sequentially as determined by the clinician. Thus, the pyridoxamine and LMWH may be combined prior to administration to a patient (ie: in a dosage unit), or the composition may comprise a co-administered dosage of two separate dosage forms. Dosage unit forms of the pyridoxamine component of the compositions of the present invention comprise between 25 mg and 1000 mg of pyridoxamine, or a pharmaceutically acceptable salt thereof. Such dosage unit forms can comprise, for example, 25, 50, 75, 100, 125, 150, 175, 200, 250, 300, 350, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, or 1000 mg of pyridoxamine, or a pharmaceutically acceptable salt thereof, or any range of such dosage unit forms. In a preferred embodiment, the dosage unit forms of the pharmaceutical compositions comprise between 50 mg and 500 mg of pyridoxamine, or a pharmaceutically acceptable salt thereof. Such dosage unit forms can comprise, for example, 50, 75, 100, 125, 150, 175, 200, 250, 300, 350, 400, 450, or 500 mg of pyridoxamine, or a pharmaceutically acceptable salt thereof. The dosage unit form can be selected to accommodate the desired frequency of administration used to achieve a specified daily dosage of pyridoxamine, or a pharmaceutically acceptable salt thereof to a patient in need thereof. Preferably the unit dosage form is prepared for once daily or twice daily administration to achieve a daily dosage of between 50 and 2000 mg, more preferably between 100 and 1000 milligrams, and even more preferably between 100 and 500 milligrams.

Dosage unit forms of the LMWH component of the compositions of the present invention comprise between 100 mg and 2000 mg of LMWH, such as sulodexide, or a pharmaceutically acceptable salt thereof. Such dosage unit forms can comprise, for example, 100, 125, 150, 175, 200, 250, 300, 350, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1250, 1500, 1750, 2000 mg of LMWH, such as sulodexide, or a pharmaceutically acceptable salt thereof, or any range of such dosage unit forms. In a preferred embodiment, the dosage unit forms of the pharmaceutical compositions comprise between 50 mg and 500 mg of sulodexide, or a pharmaceutically acceptable salt thereof; more preferably, the dosage unit forms of the pharmaceutical compositions comprise between 200 mg and 400 mg of sulodexide, or a pharmaceutically acceptable salt thereof. Such dosage unit forms can comprise, for example, 50, 75, 100, 125, 150, 175, 200, 250, 300, 350, 400, 450, or 500 mg of sulodexide, or a pharmaceutically acceptable salt thereof. The dosage unit form can be selected to accommodate the desired frequency of administration used to achieve a specified daily dosage of sulodexide, or a pharmaceutically acceptable salt thereof to a patient in need thereof. Preferably the unit dosage form is prepared for once daily or twice daily administration to achieve a daily dosage of between 50 and 2000 mg, more preferably between 100 and 1000 milligrams, and even more preferably between 200 and 400 milligrams.

Pharmaceutically acceptable salts in accordance with the present invention are the salts with physiologically acceptable bases and/or acids well known to those skilled in the art of pharmaceutical technique. Suitable salts with physiologically acceptable bases include, for example, alkali metal and alkaline earth metal salts, such as sodium, potassium, calcium and magnesium salts, and ammonium salts and salts with suitable organic bases, such as methylamine, dimethylamine, trimethylamine, piperidine, morpholine and triethanolamine. Suitable salts with physiologically acceptable acids include, for example, salts with inorganic acids such as hydrohalides (especially hydrochlorides or hydrobromides), sulphates and phosphates, and salts with organic acids.

In all aspects of the compositions of the present invention, the compounds are combined with one or more pharmaceutically acceptable carriers appropriate for the indicated route of administration. The compounds may be admixed with lactose, sucrose, starch powder, cellulose esters of alkanoic acids, stearic acid, talc, magnesium stearate, magnesium oxide, sodium and calcium salts of phosphoric and sulphuric acids, acacia, gelatin, sodium alginate, polyvinylpyrrolidine, and/or polyvinyl alcohol, and tableted or encapsulated for conventional administration. Alternatively, the compounds of this invention may be dissolved in saline, water, polyethylene glycol, propylene glycol, carboxymethyl cellulose colloidal solutions, ethanol, corn oil, peanut oil, cottonseed oil, sesame oil, tragacanth gum, and/or various buffers. Other adjuvants and modes of administration are well known in the pharmaceutical art. The carrier or diluent may include time delay material, such as glyceryl monostearate or glyceryl distearate alone or with a wax, or other materials well known in the art.

In a preferred embodiment, the compositions of the invention are prepared for oral administration. As such, the composition can be in the form of, for example, a tablet, a hard or soft capsule, a lozenge, a cachet, a dispensable powder, granules, a suspension, an elixir, a liquid, or any other form reasonably adapted for oral administration. The compositions can further comprise, for example, buffering agents. Tablets, pills and the like additionally can be prepared with enteric coatings. Unit dosage tablets or capsules are preferred. Compositions suitable for buccal administration include, for example, lozenges comprising pyridoxamine and sulodexide, or pharmaceutically acceptable salts thereof and a flavored base, such as sucrose, acacia tragacanth, gelatin, and/or glycerin.

Liquid dosage forms for oral administration can comprise pharmaceutically acceptable emulsions, solutions, suspensions, syrups, and elixirs containing inert diluents commonly used in the art, such as water. Such compositions can also comprise, for example, wetting agents, emulsifying and suspending agents, and sweetening, flavoring, and perfuming agents.

These compositions can be prepared by any suitable method that includes the step of bringing into association pyridoxamine and LMWH, or pharmaceutically acceptable salts thereof, and the pharmaceutically acceptable carrier. In general, the compositions are prepared by uniformly and intimately admixing the pyridoxamine and LMWH, or pharmaceutically acceptable salts thereof, with a liquid or finely divided solid carrier, or both, and then, if necessary, shaping the product. For example, preparation of tablets can comprise compressing or molding a powder or granule of the compound. Compressed tablets can be prepared by compressing, in a suitable machine, the compound in a free-flowing form, such as a powder or granules optionally mixed with a binding agent, lubricant, inert diluent and/or surface active/dispersing agent(s). Molded tablets can be made by molding, in a suitable machine, the powdered compound moistened with an inert liquid diluent.

In a second aspect, the present invention provides methods for treating or inhibiting development of diabetic kidney disease, comprising administering to a hyperglycemic subject in need thereof an amount effective to treat or inhibit development of one or more diabetic kidney diseases of a composition according to any embodiment of the first aspect of the invention. Such diabetic kidney diseases include, but are not limited to, hyperglycemia, hyperlipidemia., diabetic nephropathy, proteinuria, impaired glomerular clearance, retinopathy, neuropathy, atherosclerosis, diabetes-associated hyperlipidemia, oxidative modification of proteins, arthritis, connective tissue diseases, amyloidosis, urinary stone disease, obesity-related complications, proliferation of smooth muscle cells in the aorta, coronary artery occlusion, and hypertension; and dialysis-related disorders including dialysis-related cardiac morbidity and mortality, dialysis-related amyloidosis, dialysis-related increases in permeability of the peritoneal membrane in a dialysis patient, renal failure progression in a dialysis patient, and ultrafiltration failure and peritoneal membrane destruction in a dialysis patient.

In another aspect, the present invention provides methods for limiting the progression of renal disease and/or diabetic complications in a hyperglycemic subject by administering to the patient an amount effective of the composition of any embodiment of the first aspect of the invention. Such hyperglycemic subjects are mammals, such as humans.

As used herein, "hyperglycemic subject" encompasses both Type 1 and Type 2 diabetic subjects and "diabetes" encompasses both Type 1 and Type 2 diabetes.

As used herein, "limiting the progression of renal disease" means to reduce or prevent decreases in renal function in those hyperglycemic subjects receiving treatment relative to hyperglycemic subjects not receiving the treatment. Such treatment thus reduces the need for kidney dialysis or transplantation in hyperglycemic subjects.

The progression of renal disease can be measured in various ways, including the following:

(a) Proteinuria (ie: increased loss of protein into the urine; often assessed by measurement of albumin levels (ie: "albuminuria"));

(b) Impaired glomerular clearance (ie: kidney function to clear substances from blood; can be measured, for example, by creatinine (ie: "impaired creatinine clearance"), inulin, or urea clearance);

(c) Increased levels of serum creatinine; and

(d) Increased levels of urinary transforming growth factor beta (TGF-β). Thus, the methods of the invention can be used, for example, to limit the increase in one or more of proteinuria, albuminuria, serum creatinine levels, and urinary TGF-β levels, and/or to limit the impairment of glomerular clearance and/or creatinine clearance in a hyperglycemic subject being treated with pyridoxamine and LMWH or pharmaceutically acceptable salts thereof, relative to a hyperglycemic subject not receiving such treatment. As will be understood by those of skill in the art, a favorable effect of the methods of the invention on any one of these measures of renal disease constitutes limiting the progression of renal disease.

In a preferred embodiment, measuring urinary TGF-β comprises concentrating urinary samples according to standard protocols (for example, use of an Ultra-4 concentrator), and measuring the urinary concentration at a desired time point after initiation of treatment.

As used herein, "limiting the progression" of diabetic complications means slowing or stopping the progression of diabetic complications in those hyperglycemic subjects receiving treatment relative to hyperglycemic subjects not receiving the treatment. Thus, the methods of the invention can be used, for example, to slow or stop the progression of nephropathy and neuropathy in hyperglycemic subjects receiving treatment relative to hyperglycemic subjects not receiving such treatment.

As used herein, "nephropathy" refers to kidney disease, inflammation, or damage; and "neuropathy" refers to a disease, inflammation, or damage to the nervous system; symptoms include numbness, tingling, pain, or muscle weakness, depending on the nerves affected. In a further preferred embodiment, the methods serve to limit one or more symptoms of neuropathy selected from the group consisting of areflexia (reflexes absent), hyporeflexia (weakened reflexes), paresthesia (abnormal sensation, such as burning, pricking, or numbness), peripheral neuropathy (disease, inflammation, or damage to the peripheral nervous system), aggravated peripheral neuropathy, and sensory loss (partial or complete loss of sensory function).

In a further embodiment, the hyperglycemic subject being treated has microalbuminuria or macroalbuminuria. As used herein, "macroalbuminuria" is defined as having greater than 300 mg/24 h albumin excretion. As used herein, "microalbuminuria" is defined as between 30 and 300 mg/24 h albumin excretion.

In a further preferred embodiment, the hyperglycemic subject has elevated blood lipid levels, including hyperlipidemia, hypertriglyceridemia, and/or hypercholesterolemia. Such patients tend to have accelerated progression of renal disease relative to other hyperglycemic subjects, and treatment of these patients with pyridoxamine and sulodexide, or pharmaceutically acceptable salts thereof, is more effective than treatment with the current standard of care for diabetic kidney disease. In a further preferred embodiment, the hyperglycemic subject is one that has failed to adequately respond to treatment with angiotensin converting enzyme inhibitors ("ACE-I") and/or angiotensin 2 (type 1) receptor blockers ("ARBs"). As used herein, "failed to respond adequately" means that one or more measures of the progression of renal disease (proteinuria, albuminuria, serum creatinine levels, impaired glomerular clearance, impaired creatinine clearance) continue to increase despite treatment with the ACE-I and/or ARBs.

In a further preferred embodiment, the hyperglycemic subject is one with poor glycemic control. As used herein, "poor glycemic control" means that the patient has an abnormal glycated hemoglobin level. The most widely accepted measure of glycemic control is the whole blood level of hemoglobin AlC (HbAlC) (a glycosylated hemoglobin), with 6.5% HbAlC considered normal. In a preferred embodiment, the patient has a whole blood HbAlC level of greater than 6.5%; in further preferred embodiments, the patient has a whole blood HbAlC level of greater than 6.75%, 7%, 7.25%, or 7.275%. In a further embodiment, the methods further comprise administering the composition of any of the embodiments of the first aspect of the invention, in combination with a further therapeutic to limit the progression of renal disease in a hyperglycemic subject. Such therapeutics include, but are not limited to, angiotensin converting enzyme inhibitors (ACE-I), angiotensin receptor blockers (ARB), beta- blockers, aldose reductase inhibitors, calcium blockers, diuretics, insulin, insulin sensitizers, statins, fϊbrates, glucose uptake inhibitors, sulfonylureas, and protein kinase C inhibitors. The further therapeutic can be administered together as a single formulation with or separately from the pyridoxamine and LMWH, or pharmaceutically acceptable salts thereof.

Example

Diabetes mellitus is induced in 6-wk-old male Sprague-Dawley rats with streptozotocin using known protocols (see, for example, Ceol et al., J. Am. Soc. Nephrology 11 :2324-2336 (2000)). A proportion of the diabetic rats and the control rats are treated as deemed appropriate (for example, by oral administration, in drinking water, or by gavage when using a liquid preparation) with amounts of pyridoxamine and LMWH as described above, at dosing intervals deemed appropriate (for example, if gavaged, once per day), and the remaining diabetic and control rats are treated with control, such as saline, pyridoxamine alone, or LMWH alone.

Treatment is carried out for an appropriate period of time, for example, 6 months or more. After treatment for an appropriate period of time, the 24-h urinary albumin excretion rate is determined for all animals, as is the effect of treatment on glycemia, plasma creatinine levels, and albuminuria. In particular, the effects of treatment on reducing the increase in creatinine levels and on reducing albuminuria relative to control are determined.

Claims

We claim

1. A composition, comprising:

(a) an amount effective of pyridoxamine, or a pharmaceutically acceptable salt thereof for treating diabetic nephropathy; and (b) an amount effective of low molecular weight heparinoids (LMWH), or a pharmaceutically acceptable salt thereof, for treating diabetic nephropathy.

2. The composition of claim 1, wherein the LMWH comprises sulodexide.

3. The composition of claim 1 or 2, wherein the composition comprises between 25 mg and 1000 mg of pyridoxamine, or a pharmaceutically acceptable salt thereof.

4. The composition of any one of claims 1-3, wherein the composition comprises between 100 mg and 2000 mg of sulodexide, or a pharmaceutically acceptable salt thereof.

5. A pharmaceutical composition comprising the composition of any one of claims 1-4 and a pharmaceutically acceptable carrier thereof.

6. A method for treating or inhibiting development of diabetic kidney disease, comprising administering to a hyperglycemic subject in need thereof an amount effective to treat or inhibit development of one or more diabetic kidney diseases of a composition according to any one of claims 1-5.

7. A method for limiting progression of renal disease, comprising administering to a hyperglycemic subject in need thereof an amount effective to limit progression of renal disease of a composition according to any one of claims 1-5.

8. The method of claim 6 or 7 wherein the hyperglycemic subject suffers from Type 2 diabetes.

9. The method of claim 8, wherein the diabetic kidney disease or renal disease comprises diabetic nephropathy.

10. The method of claim 9 wherein the hyperglycemic subject has microalbuminuria or macroalbuminuria.

11. The method of claim 10, wherein the method slows the increase in serum creatinine levels and reduces proteinuria relative to control.

12. The method of claim 11 , wherein the hyperglycemic subject is being treated with angiotensin converting enzyme inhibitor therapy.

13. The method of claim 12, wherein the hyperglycemic subject has failed to respond adequately to angiotensin converting enzyme inhibitor therapy.

14. The method of claim 11 , wherein the hyperglycemic subject is being treated with angiotensin receptor blocker therapy.

15. The method of claim 14, wherein the hyperglycemic subject has failed to respond adequately to angiotensin receptor blocker therapy.